Giving birth to a symphony performance requires lots of time, talent and tuning up.

Especially for Sarah Antonsson and her neophyte role as a "Wagner tuba" player.

"Actually, it's just abut the same tubing," said Antonsson, whose dual role includes performing on French horn in University of the Pacific's Symphony Orchestra. "But it's wrapped so differently, you have to hold it almost like you hold a baby. That's the best way I know how to describe it."

Antonsson's been adapting to that unfamiliar tubing and unusual sound as conductor Nicolas Waldvogel has guided 75 musicians through rehearsals for an ambitious piece of music that's "very close to my heart."

"It's very unusual," Waldvogel said, noting the challenging, 65-minute symphony rarely is performed in locales such as the Central Valley. "It's more abstract and grandiose. It's not clear what it's about. It's about everything in the world. It's crazy. It's so ambitious and very stirring."

Written between 1887 and Bruckner's 1896 death, the symphony was dedicated to "God" but never completed. It requires the sonic heft of four "Wagner tubas."

Waldvogel had to rent them from a San Francisco company. Antonsson, 18, and Reilly Tamer, 19, both graduates of Mountain View High School, had to learn how to play them.

"It's been very exciting," said Antonsson, a freshman who also plays her French horn during Bruckner's final symphony, which she'd never heard before rehearsals began. "Not many people get to play it (the tuba). It's very different than I expected. It's difficult.

"In terms of actually playing it, I'd think of the note I wanted to play, and when I played that note it didn't come out. It can be hard to hit the right notes."

Antonsson, and Tamer, a sophomore, have resolved that by practicing together twice a week for the past month. Paul Kimble, a musician and educator, and Jennie Blomster, a Pacific professor, are the orchestra's other "Wagner tuba" specialists.

"If something was not right, we'd stop and check it out to make sure it was correct," she said.

Perfecting Bruckner's symphony has challenged Waldvogel's students in performance and endurance. They've responded to what Waldvogel characterized as the "ambitious highlight" of the students' four major 2012-13 performances.

"Particularly when they love it and get a feeling early on that it's attainable," said Waldvogel, who's in his 11th year at Pacific. "It's a hard piece. It's very complex. Very, very rich. It's tough on everybody. They've worked their violins off."

"It's been a challenge," said Kate Bassett, 43, who's recapturing her violin skills while studying music therapy at Pacific. "It's very welcome. It's complicated and quite difficult for violins, period. It's pushed me, but also moves me. It's a really spectacular piece."

Bassett, from San Francisco, is having fun, too. The mother of a 19-year-old daughter (Eden), she originally attended the San Francisco Conservatory of Music. After working in advertising for 12 years, she plans to use her Pacific degree and musical skills to assist with hospice and geriatric care.

"It's fun. It's hard," Bassett said. "It's been exciting. I feel, hey, (there) absolutely, clearly, obviously is an age difference. They haven't held that against me."

She's hanging in there: "It does require endurance, yes. By nature, there's some fatigue, but I think it holds the attention all the way through. There's no opportunity to get too restful. It really keeps you on your toes from beginning to end."

"I personally love heavy brass sections," she said. "It's one of the most exciting things about playing in an orchestra. The addition of those horns makes it more inviting and amazing. It's pretty powerful."

John Johnson, 20, a junior trumpet player from Pine Grove, acknowledged the tuba factor, too.

"Well, it isn't difficult in technical terms," said Johnson, a music education-performance student and former musical all-star at Amador High School in Sutter Creek. "It's more difficult in terms of textures and colors. Trying to create that can be difficult with Wagnerian tubas you normally don't work with."

It's not a 65-minute marathon for him, either.

"I'm very fortunate," he said. "For brass (instruments), there are still a lot of restings. The stress just comes with practice."

Johnson started playing trumpet at age 10. He's performed with chamber and youth orchestras - including three trips to Europe with the Sacramento Youth Symphony - and was a member of all-state, all-Capitol Section and all-Northern California groups.

They didn't include very-grown-up "Wagner tubas."

"It's an unusual horn," Waldvogel said. "It's slightly lower (in tone) than the French horn. It's something Wagner used in a role of the majesty of a great castle built by the gods."